Controlled coating apparatus, systems, and methods

ABSTRACT

Apparatus and systems may operate to provide a first reactant as a gas that flows under reduced atmospheric pressure to interact with a surface, such as a tool body surface, the interaction confined to a passage within the tool body, wherein the passage includes the surface and extends without interruption from an entrance end of the passage to an exit end of the passage. Additional activity may include providing a second reactant as a gas under the reduced atmospheric pressure, subsequent to the first reactant, to interact with the surface of the tool body; and repeated provision of the first and second reactants until a selected coating thickness on the surface is formed. Additional apparatus, systems, and methods are disclosed.

RELATED APPLICATION

This application is a divisional of U.S. patent application Ser. No.13/416,497, filed Mar. 9, 2012; which application is incorporated hereinby reference in its entirety and made a part hereof.

BACKGROUND

Understanding the structure and properties of geological formations canreduce the cost of drilling wells for oil and gas exploration.Measurements made in a borehole (i.e., down hole measurements) aretypically performed to attain this understanding, to identify thecomposition and distribution of material that surrounds the measurementdevice down hole. To obtain such measurements, a variety of sensorshoused in down hole tools are used. Since the down hole environment isrelatively harsh (e.g., as compared to a laboratory), these tools areoften subject to corrosion and other destructive influences.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front, cut-away view of an apparatus used in someembodiments of the invention.

FIG. 2 illustrates the repeated use of reactant-buffer groups accordingto some embodiments of the invention.

FIG. 3 illustrates apparatus, systems, and an oven according to someembodiments of the invention.

FIG. 4 illustrates apparatus, systems, and a vacuum chamber according tovarious embodiments of the invention.

FIG. 5 is a flow chart illustrating several methods according to variousembodiments of the invention.

FIG. 6 is a block diagram of an article according to various embodimentsof the invention.

DETAILED DESCRIPTION

Geological inspection tools deployed down hole are subject to banging,bumping, twisting, scratching, and other physical abuse, as well asinteraction with a variety of elements, including chemical compositionsused for drilling. These environmental influences often combine todestroy tool surfaces and surface coatings.

The result of this interaction with the environment can be an abrasivesurface, and/or one that is exposed and operates to short conductiveelectrical pathways. Various embodiments of the invention can operate toprovide a substantially holiday free coating on down hole tool surfaces,which are physically large, and sometimes difficult to access (e.g., theelectrical or hydraulic passages within a tool). For the purposes ofthis document, a “substantially holiday free coating” means a coatingformed from at least three atomic monolayers. For example, three toseven monolayers of coating can be useful for preventing corrosion, andshorting/arcing via electrical conduction. Thus, in some embodiments,the coating process is deemed complete when the coating comprises asubstantially holiday free coating.

These coatings can thus be used to help prevent chemical interactionbetween environmental fluids and tool metallurgy, as well as arcing inthe presence of conductive elements. These coatings can also be used toincrease the surface hardness of the tools, to prevent wear fromabrasive slurries and other environmental elements.

The process of atomic layer deposition (ALD) uses self-limiting chemicalreactions to build up layers of coating material in a controlled manner.Each layer may be constructed using two reactant components which arealternately applied from the gas phase. This process is sometimes usedto build semiconductor components, and is applied in a vacuum chamberwhere all surfaces are coated, because any surface exposed to the gasphase can interact with the gas phase.

The use of commercially available vacuum chambers is limiting in anumber of ways. In particular, large components cannot be treatedbecause they will not fit into the chamber. The cost of building achamber of suitable size to coat an entire down hole tool iscost-prohibitive.

As part of experimenting with various embodiments, the inventor hasdiscovered that tool body surfaces can be coated using an ALD process,with the interior surfaces of the tool body itself being used as thereactor. The process can be tailored to treat only the requiredsurfaces. Process temperatures are relatively low in comparison to heattreating, so that the design properties of the tool body matrix materialwill not be changed by the coating process. Indeed, the coating processconditions are usually within tool operating temperatures. Thus, variousembodiments are well suited for the application of a protective coatingto down hole tool surfaces.

FIG. 1 is a front, cut-way view of an apparatus 100 used in someembodiments of the invention. In this case, the apparatus 100 representsa down hole tool with several passages 112 that are entirely containedwithin the tool body 102, which may comprise metal.

Any number of passages 112 may exist in the tool body 102. For example,a first passage 112 might comprise a reservoir fluid path, a secondpassage 112 might comprise an electrical wiring path, and a thirdpassage 112 might comprise a hydraulic fluid path. The passages 112 maybe substantially straight, or sinuous. Passages 112 may includevariations 114 that provide an intricate intersection of irregularinterior passage surfaces 120. Examples of these different types ofpassages 112, and their variations 114, are shown in the figure.

Different passages 112 might be coated with correspondingly differentcoatings. To apply a coating 122 to the interior surface 120 of aselected passage 118, the ends of the selected passage 118 can becoupled to flow tubes 124 at an entrance end 104 and an exit end 108 ofthe passage 118, so that reactant R entering and leaving the passage 118via the flow tubes 124 can interact with the interior surface 120 of thepassage 118 that might otherwise be difficult to access. Passages 112that are not to be coated can be masked, or sealed off using end caps116.

Thus, to coat a selected passage 118, quantities of reactants R (e.g., afirst reactant followed by a second reactant) may be provided to formthe coating 122 on the surface 120. Providing a quantity of anindividual reactant R may comprise directing the flow of some amount ofthe reactant R as a gas through the selected passage 118 disposed withinthe tool body 102 over some selected amount of time.

Some reactions between the selected reactant R and the surface 120 maybe effective at or above atmospheric pressure. In some embodiments, thetemperature of the tool body 102 is changed to modify the pressurewithin the selected passage 118 so that the reactant provided is in thegas phase.

The reactant R may be mixed in a diluting gas to bring the reactant outof the liquid phase and into the gas phase. For example, water isrelatively stable at 25 C. Bubbling nitrogen through the water at 25° C.can bring the water up into the gas phase, where maximum dilution isusually driven by the temperature of the liquid phase. The liquid-gassystem can be further diluted with gas to attain a reactant Rconcentration below saturation (usually at about 50% relative humidity).The original gas stream (e.g., coupled to the flow tube 124, and storedin an external tank, as shown in FIGS. 3 and 4) should not be permittedto encounter cold spots, defined as temperatures below the bubblertemperature, since the undiluted gas may condense, leading to poorcoating uniformity. Diluted liquid-gas systems will generally toleratecooler temperatures before condensing.

In some embodiments, coating methods include the activities of maskingthe surface 120 to prevent coating selected areas of the surface 120,and etching the coating that has been applied. Generally, all exposedsurfaces 120 within the selected passage 118 are coated (assuming anexcess of each gas phase reactant is provided).

FIG. 2 illustrates the repeated use of reactant-buffer groups 200according to some embodiments of the invention. A buffer serves to helpprevent the reactants from nixing in the gas phase and reacting witheach other. Here reactants R1, R2 are separated by buffers B and N2,which may comprise nitrogen, and all of the components are provided in atrain of gas components, as part of the group 200. In some embodiments,the same buffer B is used to separate the reactants R1, R2. In someembodiments (as shown here), a buffer B of one composition follows theintroduction of reactant R1, and a buffer N2 of another compositionfollows the introduction of reactant R2.

In an example embodiment, reactant R1 (e.g., an organometallic compound,such as methyl aluminide) is added at the entrance end of a passage in atool body until a response indicating the presence of the reactant R1 isdetected at a quartz micro balance (QMB) coupled to an exit end of thepassage. The supply of reactant R1 is then cut off. In many embodiments,processes operate at a “reduced atmospheric pressure”, which for thepurposes of this document means a pressure within a range from justunder atmospheric pressure (e.g., less than 760 torr), to about 20microns of vacuum.

A purge buffer, such as a quantity of nitrogen (e.g., N2) is then addedto the passage. Afterward, a relatively small quantity of reactant R2(e.g., water vapor or hydrogen peroxide) is released into the entranceend of the passage, in an amount that is insufficient to totally coatthe surface of the passage. Additional quantities of reactant R2 arethen released, until a response is rendered by the QMB. The sum of thequantities of reactant R2 at this point is the total amount used tocreate a layer of the coating on the surface of the passage. To applyanother layer, the total quantity of reactant R1 previously applied isagain released into the passage, perhaps increased by a small amount(e.g., about 5% to about 15% more than is required to coat the surface).This produces a more rapid and complete reaction by reducing theconcentration depletion caused by transverse diffusion at the edge ofthe buffer, which exhibits a concentration gradient driven by diffusionand dispersion as it travels down the passage.

The amount of purge buffer gas B, N2 to use between reactants R1, R2 canbe determined by measuring the density of the gas leaving the exit endof the passage. As the initial reactant R1 is blown out by the buffer B,the concentration of each component at the exit end of the passage willaffect the density of the result. The transition time from pure reactantR1 to pure buffer B, and the transition time from pure buffer B toreactant R2, added together, gives the minimum amount of buffer B to usein terms of time, for a given flow rate. An excess of 10% above thisminimum amount may be useful in some embodiments. Flow rate will drivedispersion, so that larger amounts of buffer gas will be used at higherflow rates.

As a buffer gas, Nitrogen is plentiful and generally not a participantin the chemistries of the reactants. Any inert gas can be used as abuffer, such as helium, neon, xenon, and argon, as long as there islittle or no reaction with the base material to be coated, or thereactant chemistries.

Once the quantities of reactant R1, buffers B, N2, and reactant R2 areknown, the process of adding groups 200 of the reactants R1, R2 andbuffers B, N2 to the passage can be repeated to build up any desirednumber of layers. For example, in some embodiments, a coating thicknessof 100 angstroms may take approximately 40 minutes to develop, withindividual reaction cycles (e.g., the time of release for a givenreactant) being on the order of about one to about ten seconds.

In some embodiments, the reactant R1 comprises a silane, and thereactant R2 comprises methane or carbon monoxide. In some embodiments,the composition of reactants R1 and R2 are the same. The composition ofthe coating applied to the surface of a tool body passage depends on thecomposition of the reactants and the tool body itself. Thus, coatingchemistries include oxides, such as aluminum oxide (e.g., Al₂0₃, Al₂0₃),nitrides, and metals.

Therefore, in some embodiments, a metallic tool body may be coated withan oxide. In this case, the tool body comprises metal, and the coatingcomprises an oxide. In this way, a variety of embodiments may berealized.

For example, FIG. 3 illustrates apparatus 100, systems 364, and an oven374 according to some embodiments of the invention. FIG. 4 illustratesapparatus 100, systems 464, and a vacuum chamber 482 according tovarious embodiments of the invention.

Depending on the system 364, 464 chosen to coat tool body surfaces,passages within the tool body 102 may have two closed ends (e.g., bothends connected to flow tubes 124, as shown in FIG. 3), or a closed endand an open end (e.g., one end connected to a flow tub 124, and theother left open, as shown in FIG. 4).

In each case, the reactants R1, R2 (and/or a buffer B) travel along apath 376 defined in part by one or more passages in the tool body 102,and the flow tubes 124. The apparatus 100 may comprise a down hole toolinstalled as a section or as a single sub in an oven 374, such as adispatch test oven. One or more gas injection valves 372 can be used tocontrol the introduction of the reactants R1, R2 and buffer B into theentrance end 104 of a passage 118 in the tool body 102, and ameasurement device “MD” 342 is used to detect the presence of thereactants R1, R2 (and perhaps the buffer B) at the exit end 108 of thepassage 118 in the tool body 102.

In some embodiments, the measurement device 342 is directly coupled tothe exit end 108 of the passage 118 (see FIG. 3). In some embodiments,the measurement device 342 is indirectly coupled to the exit end 108 ofthe passage 118 (see FIG. 4).

The measurement device 342, which may comprise a QMB, may be coupled toa sump (e.g., a reaction screen sump comprising steel wool in a pipe)344 and a vacuum pump 346.

In some embodiments, the systems 364, 464 comprise one or moreprocessors 330, memory 350, and data acquisition logic 340. The logic340 and memory 350 may form part of a data acquisition system 352.

The memory 350 can be used to store acquired data, process recipes, andother data (e.g., in a database 334). The memory 350 is communicativelycoupled to the processor(s) 330.

The vacuum pump 346 can be used to move the reactants R1, R2 and bufferB through the apparatus 100. Thus, the systems 364, 464 may furthercomprise the pump 346 to move the reactants R1, R2 and buffer B throughthe apparatus 100, via the flow tubing 124.

In some embodiments, the system 364 may comprise a display 396 todisplay information regarding the coating process, including coatingthickness and other data that may be obtained from the measurementdevice 342. The processor(s) 330 may be used to control the flow of thereactants R1, R2 and buffer B via one or more valves 372 along the path376 that extends from the containers of the reactants R1, R2 and bufferB through the apparatus 100, and onward through the measurement device342, the sump 344, the pump 352, and the exhaust 348. Thus, theprocessor(s) 330, coupled to the signal and data lines 378, which arecoupled in turn to the valves 372, measurement device 342, and pump 346,may be used to effect this control.

Thus, referring now to FIGS. 1-4, it can be seen that a wide variety ofapparatus and systems may be realized. For example, a system 364, 464may comprise a plurality of valves 372 to control the flow of reactantsR1, R2, a measurement device to indicate surface coating thickness, anda vacuum pump 346 to move the reactants R1, R2 along a selected passage118 within the tool body 102, to interact with a surface 120 defined bythe passage 118.

In some embodiments, a system 364, 464 comprises valves 372, includinggas valves, to control entry of first and second reactants R1, R2 into apassage 118 within a tool body 102 via at least one flow tube 124, thepassage including a surface 120 and extending without interruption froman entrance end 104 of the passage 118 to an exit end 108 of the passage118. The system 364, 464 may comprise measurement device 342 (e.g., amass measurement device or a refractive index measurement device)coupleable to the exit end 108 to indicate the thickness of a coating122 on the surface 120 as the first and the second reactants R1, R2interact with the surface 120 to form the coating 122.

The system 364, 464 may also comprise a pump 352, such as a gas pump, topromote movement of the first and the second reactants R1, R2 within thepassage 118 from the entrance end 104 to the exit end 108. The system364, 464 may further comprise a sump 344, such as a screen sump or thelike, to consume residual amounts of the first and the second reactantsR1, R2, and byproducts of interaction between the first reactant R1 andthe second reactant R2. The sump 344 may be coupled to the exit end 108of the passage 118 and the pump 352.

As noted previously, gas valves 372 may be used to control the entry ofreactants R1, R2 and a buffer B into the passage 118 within the toolbody 102. In some embodiments, the gas valves 372 comprise at leastthree valves to separately control flow of the first reactant R1, thesecond reactant R2, and a buffer B into the entrance end of the passage.While only a single buffer B is shown in FIGS. 3 and 4, it should benoted that multiple buffers B having different chemical compositions maybe used to separate the introduction of the reactants R1, R2 into thepassage 118 (e.g., as shown in FIG. 2).

The coating process may be controlled by the processors 330, using anindication of the coating thickness for feedback. Thus, the system 364,464 may comprise a processor 330 to control flow of at least one of thefirst reactant R1 and the second reactant R2 based on measurementsobtained from the measurement device 342, such as a mass measurementdevice or a refractive index measurement device, or a combination ofthese.

A quartz microbalance (operating as a mass measurement device) candisplay a change in resonant frequency to indicate coating thickness. Anellipsometer (operating as a refractive index measurement device) candisplay a refractive index change of the coating to indicate coatingthickness. Thus, in some embodiments, the system 364, 464 may comprise adisplay 396 to publish a frequency change or a refractive index changeindicating the thickness of the coating.

An oven 374 may be used to raise the tool body temperature, enhancingthe speed of activity for selected reactants R1, R2. Thus, in someembodiments, the system 364, 464 may comprise an oven 374 to heat thetool body 102.

In many embodiments, no vacuum chamber 482 is used to coat the passages118 of the tool body 102. However, in some embodiments, the entire toolbody 102 may be housed in a vacuum chamber 482 for outer surface coatingtasks. Thus, in some embodiments, the system 364, 464 may comprise avacuum chamber 482 to house the tool body 102.

The apparatus 100; tool body 102; entrance end 104; exit end 108;passages 112, 118; variations 114; end caps 116; surfaces 120; flowtubes 124; reactant-buffer groups 200; processors 330; logic 340;measurement device 342; sump 344; pump 346; exhaust 348; memory 350;data acquisition system 352; systems 364, 464; valves 372; oven 374;path 376; signal and data lines 378; display 396; vacuum chamber 482;buffers B, N2; and reactants R, R1, R2 may all be characterized as“modules” herein. Such modules may include hardware circuitry, and/or aprocessor and/or memory circuits, software program modules and objects,and/or firmware, and combinations thereof, as desired by the architectof the apparatus 100 and systems 364, 464, and as appropriate forparticular implementations of various embodiments.

For example, in some embodiments, such modules may be included in anapparatus and/or system operation simulation package, such as a softwareelectrical signal simulation package, a power usage and distributionsimulation package, a power/heat dissipation simulation package, aradiation simulation and/or fluid flow package, a communicationssimulation package, a chemical reaction simulation package, and/or acombination of software and hardware used to simulate the operation ofvarious potential embodiments.

It should also be understood that the apparatus and systems of variousembodiments can be used in applications other than for down hole toolpassage coating operations, and thus, various embodiments are not to beso limited. The illustrations of apparatus 100 and systems 364, 464 areintended to provide a general understanding of the structure of variousembodiments, and they are not intended to serve as a completedescription of all the elements and features of apparatus and systemsthat might make use of the structures described herein. Some embodimentsinclude a number of methods.

For example, FIG. 5 is a flow chart illustrating several methods 511according to various embodiments of the invention. The methods 511 maycomprise processor-implemented methods, and may include, in someembodiments, methods for applying a coating of controlled thickness toselected tool body surfaces, such as drilled flow passages within a toolbody. Other operational arrangements are possible.

Depending on the construction of the apparatus in use, the tool bodypassage(s) may have two closed ends (e.g., both connected to flow tubes,as shown in FIG. 3), or a closed end and an open end (e.g., one endconnected to a flow tube, and the other left open, as shown in FIG. 4).The following description of a method embodiment assumes that the toolbody passage to be coated has two closed ends. If the tool body passagehas an open end, those of ordinary skill in the art, after reading thisdisclosure and studying the attached figures, will understand how themethod 511 can be adapted to revise the order of activities and to maskselected areas on the tool body surfaces to prevent coating of themasked areas.

Thus, a method 511 of applying a protective coating to a surface definedby a passage within a down hole tool body may begin at block 521. Themethod 511 may continue on to block 525 with heating the tool body,perhaps to enhance the speed of coating thickness development. Thus, theactivity at block 525 may comprise heating the tool body to atemperature of about 25° C.; to about 200° C. prior to providing thefirst quantity of reactant to the passage within the tool body.

Pressure within the tool body may be reduced (e.g., using a vacuum pump)to encourage the flow of reactants from one end of the tool body to theother. Thus, the method 511 may continue on to block 529 to includereducing pressure within the passage contained within the tool body topromote flow of at least one of the first reactant or the secondreactant from the entrance end to the exit end of the passage.

The method 511 may continue on to block 533 to include providing a firstquantity of the first reactant as a gas that flows under reducedatmospheric pressure to interact with a surface of a tool body, so thatthe interaction is confined to a passage within the tool body. Thepassage includes the surface, and the passage extends withoutinterruption from the entrance end of the passage to the exit end of thepassage. When an open-ended passage is coated, it is possible to coat anouter surface of the tool body at substantially the same time.

As noted previously, portions of the tool body surfaces can be maskedoff to prevent interaction with the reactants. Thus, the activity atblock 533 may comprise providing the first quantity of the firstreactant to interact with the surface of the passage, except for amasked portion of the surface to prevent forming the coating on themasked portion. Portions of the outer surface of the tool body can alsobe masked off.

Flow tubes can be used to couple the reactants directly to the toolbody, including to a passage within the tool body. Thus, the activity atblock 533 may comprise flowing the gas into a flow tube coupled to thepassage.

If the quantity of the first reactant to be used in the process is notyet known, and the presence of the first reactant is not detected at theexit end of the passage (e.g., using a measurement device describedpreviously) at block 537, then the method 511 may include returning toblock 533, so that more of the first reactant can be provided. If thedesired total quantity of the first reactant has been introduced intothe passage, as determined by quantity measurement, or detection atblock 537, then the method 511 may continue on to block 541.

Thus, in some embodiments, the first reactant may be provided at one endof the passage, until its presence is detected at the other end.Therefore, the activity at block 533 may comprise providing the firstquantity until presence of the first reactant is indicated proximate tothe exit end of the passage using a mass measurement or an index ofrefraction measurement.

A buffer may be used to purge the first reactant from a portion of thepassage, or the entire passage, prior to the introduction of the secondreactant. Thus, the method 511 may continue on to block 541 to includeproviding a buffer under reduced atmospheric pressure subsequent to thefirst reactant, and prior to the second reactant, to substantially purgethe first reactant from at least a portion of the passage.

The method 511 may continue on to block 545 to include providing asecond quantity of a second reactant as a gas under reduced atmosphericpressure, subsequent to the first quantity of the reactant, to interactwith the surface of the tool body passage. Early in the process, insteadof providing the entire quantity of the second reactant all at once, thesecond reactant can be provided in a series of smaller amounts while theexit end of the passage is monitored for presence of the secondreactant, to determine when the passage has been coated using the secondreactant and thus, an optimal total amount of the second reactant thatis sufficient to coat the desired surface. In other words, the smalleramounts of the second reactant, each taken alone, are less than what isneeded to coat the entire surface of the tool body passage that hasalready been coated by the first reactant. However, once the presence ofthe second reactant is detected, the total amount of the second reactantused to accomplish coating will be the sum of the smaller amounts. Thus,the activity at block 545 may comprise providing a portion of the secondquantity in an amount insufficient to coat a portion of the surface thathas interacted with the first quantity.

Many reactants can be used. A partial list includes one or more of thefollowing: an aluminum compound, a barium compound, a cadmium compound,a carbon compound, a chromium compound, a cobalt compound, a coppercompound, a gallium compound, a gold compound, an indium compound, aniron compound, a magnesium compound, a nickel compound, an oxygencompound, a platinum compound, a silicon compound, a silver compound, atin compound, a titanium compound, a vanadium compound, or a zinccompound.

The method 511 may continue on to block 549 to include providing a totalamount of the second quantity of reactant by repeatedly providing anadditional amount of the second quantity until presence of the secondreactant is indicated proximate to the exit end of the passage (e.g.,via direct coupling of a measurement device to the exit end of thepassage, per FIG. 3, or via indirect coupling of the measurement deviceto the exit end of the passage, per FIG. 4).

In some embodiments, the method 511 may continue on to block 553 toprovide a buffer after the total amount of the second quantity of thereactant has been introduced into the passage. The composition of thebuffer provided as part of the activity in block 553 may be the same as,or different from, the buffer provided as part of the activity in block541.

In some embodiments, the method 511 may continue on to block 557 toinclude determining the thickness of the coating, which may comprise oneor more atomic monolayers. The activity at block 557 may includepublishing (e.g., via workstation display, hardcopy printout, ornonvolatile memory storage) the indicated or approximate thickness ofthe coating.

The method 511 may continue on to block 561 to determine whether thedesired coating thickness has been achieved. If not, then the method 511may comprise returning to block 533, to include repeating providing thefirst quantity and the second quantity of the reactants (and buffers, ifdesired) until a selected coating thickness on the surface is formed.

As noted previously, the coating thickness may be determined by thenumber of monolayers that have been formed. Thus, the first and secondreactants may be provided repeatedly to form the coating as a selectednumber of monolayers to obtain the selected thickness.

Repeating groups of reactants, separated by one or more buffers, can bedeployed along the distance of the passage, from the entrance end to theexit end. Thus, the repetition of activity within the method 511 maycomprise repeatedly sending a series of groups through the passage, thegroups comprising the first reactant, a buffer, the second reactant, andthe same buffer, or a different buffer.

Once the desired coating thickness has been achieved, the method 511 mayend at block 565.

It should be noted that the methods described herein do not have to beexecuted in the order described, or in any particular order. Moreover,various activities described with respect to the methods identifiedherein can be executed in iterative, serial, or parallel fashion. Thevarious elements of each method (e.g., the methods shown in FIG. 5) canbe substituted, one for another, within and between methods.Information, including parameters, commands, operands, and other data,can be sent and received in the form of one or more carrier waves.

Upon reading and comprehending the content of this disclosure, one ofordinary skill in the art will understand the manner in which a softwareprogram can be launched from a computer-readable medium in acomputer-based system to execute the functions defined in the softwareprogram. One of ordinary skill in the art will further understand thevarious programming languages that may be employed to create one or moresoftware programs designed to implement and perform the methodsdisclosed herein. The programs may be structured in an object-orientatedformat using an object-oriented language such as Java or C#. In anotherexample, the programs can be structured in a procedure-orientated formatusing a procedural language, such as assembly or C. The softwarecomponents may communicate using any of a number of mechanisms wellknown to those skilled in the art, such as application programinterfaces or inter-process communication techniques, including remoteprocedure calls. The teachings of various embodiments are not limited toany particular programming language or environment. Thus, otherembodiments may be realized.

For example, FIG. 6 is a block diagram of an article 600 according tovarious embodiments of the invention, such as a computer, a memorysystem, a magnetic or optical disk, or some other storage device. Thearticle 600 may include one or more processors 616 coupled to amachine-accessible medium such as a memory 636 (e.g., removable storagemedia, as well as any tangible, non-transitory memory including anelectrical, optical, or electromagnetic conductor) having associatedinformation 638 (e.g., computer program instructions and/or data), whichwhen executed by one or more of the processors 616, results in aspecific machine (e.g., the article 600) performing any actionsdescribed with respect to the methods of FIG. 5, the apparatus of FIG.1, and/or the systems 364, 464 of FIGS. 3 and 4. The processors 616 maycomprise one or more processors sold by Intel Corporation (e.g., Intel®Core™ processor family), Advanced Micro Devices (e.g., AMD Athlon™processors), and other semiconductor manufacturers.

In some embodiments, the article 600 may comprise one or more processors616 coupled to a display 618 to display data processed by the processor616 and/or a wireless transceiver 620 (e.g., a local transmitter coupledto a data acquisition system) to receive and transmit data processed bythe processor to another (remote) system.

The memory system(s) included in the article 600 may include memory 636comprising volatile memory (e.g., dynamic random access memory) and/ornon-volatile memory. The memory 636 may be used to store data 640processed by the processor 616.

In various embodiments, the article 600 may comprise communicationapparatus 622, which may in turn include amplifiers 626 (e.g.,preamplifiers or power amplifiers) and one or more antenna 624 (e.g.,transmitting antennas and/or receiving antennas). Signals 642 receivedor transmitted by the communication apparatus 622 may be processedaccording to the methods described herein.

Many variations of the article 600 are possible. For example, in variousembodiments, the article 600 may comprise a data acquisition andprocessing system, including the apparatus 100 shown in FIG. 1. In someembodiments, the article 600 is similar to or identical to portions ofthe systems 364, 464 shown in FIGS. 3 and 4.

Using the apparatus, systems, and methods disclosed herein may enablecost-effective coating of passages within large objects, such as downhole tool bodies, that are difficult to access using prior art methods.The application of a protective, holiday free coating may provide anumber of advantages, such as reducing H₂S adsorption in the tool.Another advantage may include reducing the tendency to form abrasivesurfaces, which in turn may reduce cable wear and the potential forarcing. Increased customer satisfaction may result.

The accompanying drawings that form a part hereof, shown by way ofillustration, and not of limitation, specific embodiments in which thesubject matter may be practiced. The embodiments illustrated aredescribed in sufficient detail to enable those skilled in the art topractice the teachings disclosed herein. Other embodiments may beutilized and derived therefrom, such that structural and logicalsubstitutions and changes may be made without departing from the scopeof this disclosure. This Detailed Description, therefore, is not to betaken in a limiting sense, and the scope of various embodiments isdefined only by the appended claims, along with the full range ofequivalents to which such claims are entitled.

Such embodiments of the inventive subject matter may be referred toherein, individually and/or collectively, by the term “invention” merelyfor convenience and without intending to voluntarily limit the scope ofthis application to any single invention or inventive concept if morethan one is in fact disclosed. Thus, although specific embodiments havebeen illustrated and described herein, it should be appreciated that anyarrangement calculated to achieve the same purpose may be substitutedfor the specific embodiments shown. This disclosure is intended to coverany and all adaptations or variations of various embodiments.Combinations of the above embodiments, and other embodiments notspecifically described herein, will be apparent to those of skill in theart upon reviewing the above description.

The Abstract of the Disclosure is provided to comply with 37 C.F.R. §1.72(b), requiring an abstract that will allow the reader to quicklyascertain the nature of the technical disclosure. It is submitted withthe understanding that it will not be used to interpret or limit thescope or meaning of the claims. In addition, in the foregoing DetailedDescription, it can be seen that various features are grouped togetherin a single embodiment for the purpose of streamlining the disclosure.This method of disclosure is not to be interpreted as reflecting anintention that the claimed embodiments require more features than areexpressly recited in each claim. Rather, as the following claimsreflect, inventive subject matter lies in less than all features of asingle disclosed embodiment. Thus the following claims are herebyincorporated into the Detailed Description, with each claim standing onits own as a separate embodiment.

What is claimed is:
 1. A system, comprising: a tool body; gas valves tocontrol entry of first and second reactants via at least one flow tubeinto a passage within the tool body, the passage including a surface andextending without interruption from an entrance end of the passage to anexit end of the passage; a mass measurement device or a refractive indexmeasurement device coupleable to the exit end to indicate a thickness ofa coating on the surface as the first and the second reactants interactwith the surface to form the coating; a vacuum pump to promote movementof the first and the second reactants within the passage from theentrance end to the exit end; and a control unit including instructionsthat, when executed: cause a first quantity of a first reactant to beprovided as a gas that flows under reduced atmospheric pressure tointeract with a surface of the tool body, the interaction being confinedto the passage within the tool body, wherein providing the firstquantity comprises providing the first quantity until presence of thefirst reactant proximate to the exit end is indicated, using a massmeasurement obtained from the mass measurement device or an index ofrefraction measurement obtained from the refractive index device; causea second quantity of a second reactant to be provided as a gas underreduced atmospheric pressure, subsequent to the first quantity, tointeract with the surface of the tool body; and cause providing of thefirst quantity and the second quantity to be repeated until a selectedthickness of a coating on the surface is formed.
 2. The system of claim1, further comprising: a sump to consume residual amounts of the firstand the second reactants and byproducts of interaction between the firstreactant and the second reactant, the sump coupled to the exit end ofthe passage and the vacuum pump.
 3. The system of claim 1, wherein thegas valves comprise at least three valves to separately control flow ofthe first reactant, the second reactant, and a buffer into the entranceend of the passage.
 4. The system of claim 1, further comprising: aprocessor to control flow of at least one of the first reactant and thesecond reactant based on measurements obtained from the mass measurementdevice or the refractive index measurement device.
 5. The system ofclaim 1, further comprising: a display to publish a frequency change ora refractive index change indicating the thickness of the coating. 6.The system of claim 1, further comprising: a vacuum chamber to house thetool body.
 7. The system of claim 1, further comprising: an oven to heatthe tool body.